数据结构——链表学习笔记

public class IntNode
{
    public static void main(String[] args)
    {
        IntNode shortList;
        IntNode copy;
        shortList = new IntNode(10,null);
        shortList.addNodeAfter(20);
        shortList.addNodeAfter(25);
        shortList.addNodeAfter(30);
        shortList.addNodeAfter(38);
        shortList.addNodeAfter(42);
        shortList.addNodeAfter(55);
        // IntNode.listCopy()测试
        copy = IntNode.listCopy(shortList);
        System.out.println(IntNode.listLength(copy));
        System.out.println(IntNode.listLength(shortList));
        // IntNode.listCopyWithTail测试
        IntNode[] copyWithTail = IntNode.listCopyWithTail(shortList);
        System.out.println(copyWithTail[0].getData());
        System.out.println(copyWithTail[1].getData());
        // IntNode.listData(IntNode head)测试
        for (int i = 0 ; i < IntNode.listLength(copy) ; i++ )
        {
            System.out.print(i + 1 + ": " + IntNode.listData(shortList)[i] + "; ");
        }
        // IntNode.listPart(IntNode start,IntNode end)测试
        System.out.println("--------------------------");
        try
        {
            IntNode[] listPartCopy = IntNode.listPart(shortList,new IntNode(42,null),new IntNode(25,null));
            
            System.out.println(listPartCopy[0].getData());
            System.out.println(listPartCopy[1].getData());
        }
        catch (IllegalArgumentException e)
        {
            e.printStackTrace();
        }
        
        // IntNode.listPostion(IntNode head,int position)测试
        System.out.println("-------------------------");
        try
        {
            System.out.println("Position 5: " + IntNode.listPosition(shortList,5).getData());
        }
        catch (IllegalArgumentException e)
        {
            e.printStackTrace();
        }
    }
    int data;
    IntNode link;
    public IntNode(int data,IntNode link)
    {
        this.data = data;
        this.link = link;
    }
    public int getData()
    {
        return this.data;
    }
    public void setData(int data)
    {
        this.data = data;
    }
    public IntNode getLink()
    {
        return this.link;
    }
    public void setLink(IntNode link)
    {
        this.link = link;
    }
    public void addNodeAfter(int element)
    {
        link = new IntNode(element,link);
    }
    public void removeNodeAfter()
    {
        link = link.link;
    }
    public static int listLength(IntNode head)
    {
        int answer = 0;
        IntNode cursor;        
        if (head == null)
        {
            return answer;
        }
        for (cursor = head ; cursor != null ; cursor = cursor.getLink())
        {
            answer++;
        }
        return answer;
    }
    public static IntNode listCopy(IntNode source)
    {
        IntNode copyHead = null;
        IntNode copyTail = null;
        
        if (source == null)
        {
            return null;
        }
        copyHead = new IntNode(source.getData(),null);
        copyTail = copyHead;
        while ((source = source.getLink()) != null) //书上代码为：while(source.link != null)
        {
            IntNode copyTemp = new IntNode(source.getData(),copyTail.getLink()); 
            copyTail.link = copyTemp;
            copyTail = copyTemp;
            // 上为自己构思的方法，这个相当于copyTail一直向后加
            // 以下书上的源代码
            //source = source.link;
            //copyTail.addNodeAfter(source.getData());
            //copyTail = copyTail.getLink();
        }
        return copyHead;
    }
    public static IntNode[] listCopyWithTail(IntNode source)
    {
        IntNode copyHead = null;
        IntNode copyTail = null;
        IntNode[] answer = new IntNode[2];
        if (null == source)
        {
            return answer;
        }
        copyHead = new IntNode(source.getData(),null);
        copyTail = copyHead;
        answer[0] = copyHead;
            System.out.println("-----------------------------");
        while ((source = source.getLink()) != null)
        {
            System.out.println("source data:" + source.getData());
            //copyTail = new IntNode(source.getData(),copyTail.getLink());
            copyTail.link = new IntNode(source.getData(),copyTail.getLink()); 
            copyTail = copyTail.link;
            //copyTail.addNodeAfter(source.getData());
            //copyTail = copyTail.getLink();;
            System.out.println("copyed Tail data:" + copyTail.getData());
        }
        answer[1] = copyTail;
        return answer; 
    }
    public static IntNode[] listPart(IntNode head,IntNode start,IntNode end)
    {
        IntNode copyHead;
        IntNode copyTail;
        IntNode[] answer = new IntNode[2];
        
        if (null == start)
        {
            throw new IllegalArgumentException("start is null.");
        }
        if (null == end)
        {
            throw new IllegalArgumentException("end is null.");
        }
        copyHead = new IntNode(start.getData(),null);
        //System.out.println("start data: " + start.getData());
        //System.out.println("end data: " + end.getData());
        copyTail = copyHead;
        start = IntNode.listNodeByData(head,start.getData());
        end = IntNode.listNodeByData(head,end.getData());
        while (start != end)
        {
            start = start.getLink();
            System.out.println("start data: " + start.getData());
            if (null == start)
            {
                throw new IllegalArgumentException("end node was not found on the list.");
            }
            copyTail.link = new IntNode(start.getData(),copyTail.getLink());
            copyTail = copyTail.link;
        }
        answer[0] = copyHead;
        answer[1] = copyTail;
        return answer;
    }
    public static int[] listData(IntNode head)
    {
        int[] answer = new int[IntNode.listLength(head)];
        for (int i = 0; head != null ; head = head.link )
        {
            answer[i++] = head.getData();
        }
        return answer;
    }
    public static IntNode listNodeByData(IntNode head,int data)
    {
        if (null == head)
        {
            throw new IllegalArgumentException("list is null.");
        }
        for (; head != null ; head = head.getLink() )
        {
            if (head.getData() == data )
            {
                return head;
            }
            if (null == head)
            {
                throw new IllegalArgumentException("node not found.");
            }
        }
        return null;
    }
    public static IntNode listPosition(IntNode head,int position)
    {
        position--;
        if (null == head)
        {
            throw new IllegalArgumentException("list is null.");
        }
        if (position <= 0)
        {
            throw new IllegalArgumentException("position is not positive!");
        }
        for (int i = 0 ; (i < position) && (head != null) ; i++ )
        {
            head = head.getLink();
        }
        return head;
    }
}